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suchw

FMC wind input question yet again sigh

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Hello I have been toying around with Fsbuild and ASE and finally I have winds aloft pulled into the Fsbuild flightplan although they often do differ from the winds aloft in ASE so I would assume best to use the ASE winds aloft for the FMC input and the Fsbuild winds for fuel burn planning anybody any advice there does that sound reasonable as I am sure ASE will reflect what winds are actually in the sim the FSBUILD winds seem a bit out of wack other question I have is when i go into the legs page and hit data to enter the winds for waypoints they dont all have the dotted line so i cant add the winds, strange because on earlier FMC programming I am pretty sure all the waypoints had the capability to add wind into, of late I am only able to add winds into a few waypoints in the middle of the program, any body know what may be going on there surely you should be able to add forecast winds for each waypoint, thanks very much steep learning curve you sort one thing out and another 10 you have not grasped yet.


Wayne such

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I have noticed this also. The wind entries can only be made for the next one or two waypoints. In the 767 FMC the winds could be entered for all of the legs. Can we get the PMDG staff to weigh in on this? Maybe the fix can be added to SP1 if this is a valid issue? Don


Don Lillard

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i cant even do that if i am lucky I can add a couple of waypoints mid plan


Wayne such

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Can you explain this more? I am looking in the FCOM FMC part of the manual and cannot find what you are referring to. Is the reason that the wind cannot be entered is because it is already computed on another FMC screen such as the ACT ECON CRUZ page?


Don Lillard

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thanks Falcon999 I also cant find would you mind quoting page number


Wayne such

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I've tried this several times with a long route, while still sitting on the ground and after completing the CDU preflight. In all cases, if I continue long enough to enter winds for cruise waypoints on the RTE DATA page, the CDU will lock up and refuse to accept any more wind entries. At this point existing cruise winds are also lost, and there is also information missing in the right CDU column if I go back to the LEGS page. It does not seem to matter how the entries are made (020/05 vs 20/5, pressing EXEC after each entry vs. making multiple entries then EXEC, etc). This is the route I tried: EKCH BISTA T503 GIMRU UT503 MIC UZ707 FAMEN UZ707 BSN UZ707 RESMI UN857 TERTO GCLP. Definitely not working as intended, at least not on my computer. (The relevant page in FCOMv2 is 11.42.33).

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Take a look at page 1046 in FCOMv2 "Route and Waypoint Data". The RTE DATA page displays forecast wind data for cruise waypoints. The cruise wind data entered in the PERF INIT page (page 942 in the manual), will be propagated here. If you have exact data for each waypoint, this can also be entered here on the RTE DATA page, but only for cruise waypoints!Take a look at page 1084 in FCOMv2 for the DES FORECASTS page entries. Vital for correct descent path calculation. Personally I use Active Sky and FSBuild together for collecting waypoints wind data for both cruise waypoints and to enter forecast data for pre-descent planning.FMC12.jpg Per

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If you have exact data for each waypoint, this can also be entered here on the RTE DATA page, but only for cruise waypoints!
Except if you have enough cruise waypoints and try to enter winds for them all, you will run into problems. There does appear to be two different types of problems being discussed in this tread - (1) the FMC not being able to accept cruise wind data beyond some limit, and (2) users trying to enter descent waypoint winds on the RTE DATA page.

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Hello I have been toying around with Fsbuild and ASE and finally I have winds aloft pulled into the Fsbuild flightplan although they often do differ from the winds aloft in ASE so I would assume best to use the ASE winds aloft for the FMC input and the Fsbuild winds for fuel burn planning anybody any advice there does that sound reasonable as I am sure ASE will reflect what winds are actually in the sim the FSBUILD winds seem a bit out of wack other question I have is when i go into the legs page and hit data to enter the winds for waypoints they dont all have the dotted line so i cant add the winds, strange because on earlier FMC programming I am pretty sure all the waypoints had the capability to add wind into, of late I am only able to add winds into a few waypoints in the middle of the program, any body know what may be going on there surely you should be able to add forecast winds for each waypoint, thanks very much steep learning curve you sort one thing out and another 10 you ,have not grasped yet.
There is an issue with the weather data generated by ASE. They use point as decimal separator, so if your system uses comma instead of point, FSBuild gets the wrong winds from the ASE weather file. Check FSBuild forums. I changed my decimal separator to point, and now FSBuild reads the winds as it should.Regards,Jorge Villar

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where did you change the decimal seperator point, is this a system setting, thanks I looked over at fsbuild but confusing


Wayne such

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Except if you have enough cruise waypoints and try to enter winds for them all, you will run into problems.There does appear to be two different types of problems being discussed in this tread - (1) the FMC not being able to accept cruise wind data beyond some limit, and (2) users trying to enter descent waypoint winds on the RTE DATA page.
I'm not sure if this is a problem, as far as I know (2) is as the 'real thing'. Descent winds should be entered in the DES FORECASTS page. As for (1), I just tried to rebuild a route with 6 pages of cruise waypoints. I could easily enter cruise winds into every waypoint, se pic below. (This reminds to suggest an UPLINK function with winds data from a flight plan/navlog such as in Active Sky, as in RL, hint,hint:))FMC13.jpg Per

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I'm not sure if this is a problem, as far as I know (2) is as the 'real thing'.
Not a problem in the sense that it is something that PMDG needs to fix, no.
As for (1), I just tried to rebuild a route with 6 pages of cruise waypoints. I could easily enter cruise winds into every waypoint, se pic below.
OK, thanks for trying this. Maybe something specific to my system, then, or maybe that particular route - what route did you load? Did you press EXEC after each entry, or after entering the entire list of winds? Was this on the ground or in the air? EDIT: I can see that you left some winds on the LEGS 3/6 page the same as previous waypoint. What about the remaining pages - individual entries for each waypoint?

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Hmm, about the descent phase, what makes you think this is something that PMDG needs to fix? Isn't this modelled as in real life? Personally I think this is correct.For my route:I made a route with FSBuild from ENVA to LHBP and fetched weather data from Active Sky for the particular route and waypoints. Winds data was entered on the ground and EXEC'uted after each entry(I think)..For the remaining pages, some individual entries if needed and the rest 'propagated'. This worked for me.BUT, I tried your route, EKCH BISTA T503 GIMRU UT503 MIC UZ707 FAMEN UZ707 BSN UZ707 RESMI UN857 TERTO GCLP, generated it with FSBuild and imported to Active Sky. Entered average route wind on the PERF INIT first, then entered correct wind info for each waypoint needed as per the navlog.When I was on the 6th page, the FMC locked up and all info of winds and RTE data was lost, no chance to make new entries. Strange, probably the same issue as for you. Per

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In the 737NG : You can only enter winds for CRZ waypoints. Following Bulfer, for astronauts and engineers: For CLB predictions winds and ISA are "interpolated" from the PERF INIT entry before CLB or when predictions are related to altitudes more than 2000 ft away from current altitude. Winds are "mixed" within 2000 ft of current altitude meaning a composite wind obtained from actual wind / ISA conditions and entered wind. For CRZ predictions there exists a composite two dimensional mixing model based on distance from aircraft and difference from cruise altitude using actual and entered wind data (in LEGS / RTE DATA). The mixing function is non linear (and I am not going to publish it here for obvious reasons). For DES predictions, before descend phase, DES FORECAST entries are used in combination with PERF INIT entries (if required). Within a small distance from ToD and during descend again a vertical mixing model is used between interpolated wind entries and actual wind conditions. In general this is quite a sophisticated model and unlike most other add on's everything you enter matters and is taken into account !Therefore remember : garbage in, garbage out.


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E M V

Precision Manuals Development Group

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